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Updated: Nov 10, 2025
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
15.6K
Multiband asymmetric sound absorber enabled by ultrasparse Mie resonators
Chen Shao1, Chen Liu1, Chengrong Ma1
1Department of Physics, Key Laboratory of Modern Acoustics, Nanjing University, Nanjing 210093, China.
The Journal of the Acoustical Society of America
|April 3, 2021
Summary
This study presents an asymmetric metamaterial sound absorber with tunable Mie resonators (MRs). It achieves high sound absorption with free ventilation, overcoming a key challenge in noise elimination.
Area of Science:
- Acoustics
- Materials Science
- Metamaterials
Background:
- Developing efficient subwavelength sound absorbers with ventilation is challenging.
- Metamaterials offer unique acoustic properties but often lack ventilation capabilities.
Purpose of the Study:
- To propose and demonstrate a novel asymmetric metamaterial sound absorber.
- To achieve high sound absorption with simultaneous free air circulation.
Main Methods:
- Theoretical proposal and experimental demonstration of an asymmetric metamaterial absorber.
- Utilizing tuned Mie resonators (MRs) with unbalanced intrinsic losses.
- Fluid dynamics investigation for ventilation assessment.
Main Results:
- Achieved quasi-perfect sound absorption (95%) from one side and high reflection (71%) from the other.
- Demonstrated superior free air circulation due to ultrasparsity (5% volume filling ratio).
- Extended asymmetric absorption into multibands using multiple-order resonant modes.
Conclusions:
- The proposed asymmetric metamaterial absorber effectively tackles noise elimination while allowing ventilation.
- The design's sparsity and tunable losses are key to its performance and airflow robustness.
- This work offers a flexible methodology for designing advanced acoustic devices.
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